How to manually set a file name when I click the pdf button

How to manually set a file name when I click the pdf button

I created an html page and I enabled the pdf = true.
I would like to ask you if there is any way when I click the PDF button and starts download the file to change the name of the downloaded file. I mean if I can manually set the name of the PDF file somewhere in the html page and by clicking the PDF button to set this name to the file